You can get at them if the underlying scalars are defined: 
while (my ($sym_name, $sym_glob) = each %{"${pkg}::"}) {
    push(@things, $sym_name) if (defined ${ *$sym_glob{SCALAR} }) ;
}

[download]
Unfortunately, if they've been declared but never initialized, I can't seem to get at them in five minutes of trying. The trick you came up with for coderefs doesn't do the job here.

In reply to Re: Finding out if a scalar exists in a typeglob by chromatic
in thread Finding out if a scalar exists in a typeglob by davorg

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